Mybatis插入数据后返回自增长主键

mysql和sqlserver支持自增长字段，可使用如下方法获取插入数据的主键值

• mybatis sql管理文件，keyProperty对应User中用来存放主键值的字段，执行插入操作后，主键值会被放入parameterType的keyProperty属性中。

<insert id="insertUserAndGetUserId" useGeneratedKeys="true" keyProperty="userId" parameterType="com.study.User">
    insert into tb_user (userName,password) values (#{userName},#{password})
</insert>

• User类

package com.study;

public class User {
    private Integer userId;
    private String userName;
    private String password;

    public Integer getUserId() {
        return userId;
    }
    public void setUserId(Integer userId) {
        this.userId = userId;
    }
    public String getUserName() {
        return userName;
    }
    public void setUserName(String userName) {
        this.userName = userName;
    }
    public String getPassword() {
        return password;
    }
    public void setPassword(String password) {
        this.password = password;
    }
}